(Last week’s Calbuco eruption in Chile spews massive cloud of ash and sets off a fireworks display of volcanic lightning. Image source: IFLScience.)

If you look at the geological record of the end of the last ice age, there’s something that crops up that’s more than a little bit disturbing. The approximate 10,000 year period in which 4 degrees Celsius of warming took place was also punctuated by a rash of intense volcanic activity, earthquakes and tsunamis.

It was a time of extraordinary geophysical changes that not only saw the, sometimes catastrophic, melting of massive ice sheets and extreme rises in sea level — it also saw severe geological upheaval. In one region alone — Iceland — instances of volcanic eruption increased 30-50 fold during a period starting about 12,000 years ago. Overall, global spikes in volcanism began near the start of major melt events at around 18,000…